I've been using the app on my Nexus 5x for a couple of months with no problems. In the last few few days it won't connect. It gets past the sign in screen but then repeatedly flashes "Reconnecting" in the centre of the screen. Eventually the guide appears in the background but a "Box Not Found" warning appears. The reconnecting message still keeps flashing up. I'm able to connect to my box using the iPad app so I know the box is on the network. I've reinstalled the app but get the same message.
Thanks. I had done a full reset of my phone and it's now working - not too much of a pain as everything is backed up with Google. The app was up to date and I had tried re-installing with no luck, it's difficult to know what broke it. I had only recently added it as a streaming device (and it did work initially) so I couldn't re-register as I think you can only do that once a month.